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phase_parametrized.py
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964 lines (857 loc) · 34.9 KB
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from matplotlib import pyplot as plt
from timeseries import TimeSeries
from system_model import SystemModel
from parametrized_patterns import create_pattern_from_dict
from kinematics import ParametrizedKinematics
import casadi as ca
import numpy as np
import copy
from system_model import State
from kite import Kite
from winch import Winch
import logging
logger = logging.getLogger(__name__)
class PhaseParameterized(TimeSeries):
def __init__(
self,
kite_model: SystemModel,
quasi_steady: bool = False,
pattern_config: dict = None,
pattern_config_opti: dict = None,
sharpness_beta: float = 1e-4,
tension_min: float = 0.0,
tension_max: float = 1e5,
):
"""
Args:
"""
super().__init__(
kite_model=kite_model,
)
self.pattern_config = pattern_config
if not pattern_config_opti:
self.pattern_config_opti = copy.deepcopy(pattern_config)
else:
self.pattern_config_opti = pattern_config_opti
self.quasi_steady = quasi_steady
self.kite_model = kite_model
self.target_drag_coefficient = None
self.target_lift_coefficient = None
self.s = ca.MX.sym("s")
self.t = ca.MX.sym("t")
self.s_dot = ca.MX.sym("s_dot")
self.s_ddot = ca.MX.sym("s_ddot")
self.sharpness_beta = sharpness_beta
self.tension_min = tension_min
self.tension_max = tension_max
self.winch_model = Winch(
pattern_config=self.pattern_config["radial_parameters"]
)
pattern = create_pattern_from_dict(self.pattern_config["path_parameters"])
km_copy = self.substitute_parametrized_kinematics(pattern)
self.km_param = km_copy
# self.find_optimal_angle_pitch_tether()
def run_simulation(self, start_state, allow_failure=True, return_states=False):
# print("Starting state:", start_state)
pattern = create_pattern_from_dict(
self.pattern_config["pattern_type"], self.pattern_config["path_parameters"]
)
km_copy = self.substitute_parametrized_kinematics(pattern=pattern)
self.states = []
km_copy.reset_solver()
self.km_param = km_copy
if self.quasi_steady:
unknown_vars = ["length_tether", "input_steering", "s_dot", "speed_radial"]
else:
unknown_vars = ["length_tether", "input_steering", "s_ddot", "speed_radial"]
if km_copy.is_tether_rigid:
unknown_vars[0] = "tension_tether_ground"
# Initialize state
if isinstance(start_state, dict):
state_obj = State(**start_state)
else:
state_obj = start_state
N = self.pattern_config["n_points"]
time_step = self.pattern_config["end_time"] / self.pattern_config["n_points"]
intg = self.integrator(time_step=time_step, kite_model=km_copy)
qs_solver = self.residual_solver(km_copy)
# print("New state:", qs_solver)
if self.quasi_steady:
x0 = ca.vertcat(
state_obj.tension_tether_ground,
state_obj.input_steering,
state_obj.s_dot,
state_obj.speed_radial,
)
p = ca.vertcat(state_obj.s, state_obj.distance_radial)
lbx, ubx, lbg, ubg = km_copy.get_boundaries(state_obj, unknown_vars)
sol = qs_solver(x0=x0, p=p, lbg=lbg, ubg=ubg, lbx=lbx, ubx=ubx)
x0 = p
z0 = sol["x"]
else:
x0 = ca.vertcat(
state_obj.tension_tether_ground,
state_obj.input_steering,
state_obj.s_dot,
state_obj.speed_radial,
)
p = ca.vertcat(state_obj.s, state_obj.s_dot, state_obj.distance_radial)
lbx, ubx, lbg, ubg = km_copy.get_boundaries(state_obj, unknown_vars)
sol = qs_solver(x0=x0, p=p, lbg=lbg, ubg=ubg, lbx=lbx, ubx=ubx)
x0 = p
z0 = sol["x"]
# self.states.append(new_state.to_dict())
t = self.pattern_config["start_time"]
for i in range(N):
# print(f"Time: {t}, State: {x0}, Inputs: {z0}")
try:
sol = intg(
x0=x0,
p=t,
z0=z0,
)
except Exception as e:
print(f"Error occurred: {e}")
if not allow_failure:
raise
break
x0 = sol["xf"]
z0 = sol["zf"]
if self.quasi_steady:
new_state = State(
t=t,
s=x0[0],
input_steering=float(z0[1]),
tension_tether_ground=float(z0[0]),
s_dot=float(z0[2]),
distance_radial=float(x0[1]),
speed_radial=float(z0[3]),
)
else:
new_state = State(
t=t,
s=x0[0],
s_dot=float(x0[1]),
input_steering=float(z0[1]),
tension_tether_ground=float(z0[0]),
s_ddot=float(z0[2]),
distance_radial=float(x0[2]),
speed_radial=float(z0[3]),
)
t += time_step
self.states.append(new_state.to_dict())
def run_simulation_phase(
self, start_state, allow_failure=True, return_states=False
):
"""
March along an s-grid. At each grid point:
- solve residuals for unknowns (z)
- record state at current (t, s_i)
- if not last grid point, compute dt from ds, v, a and advance x, t.
Conventions:
QS : a_s = 0 -> ds = v_s * dt
Dyn : ds = v_s * dt + 0.5 * a_s * dt^2 (stable quadratic root used)
"""
# --- setup / housekeeping
self.kite_model.reset_solver()
pattern = create_pattern_from_dict(self.pattern_config["path_parameters"])
km_copy = self.substitute_parametrized_kinematics(pattern)
self.km_param = km_copy
self.states = []
# unknowns to solve at each s-node
if self.quasi_steady:
unknown_vars = ["length_tether", "input_steering", "s_dot", "speed_radial"]
else:
unknown_vars = ["length_tether", "input_steering", "s_ddot", "speed_radial"]
if km_copy.is_tether_rigid:
unknown_vars[0] = "tension_tether_ground"
# initial state object
state_obj = (
State(**start_state) if isinstance(start_state, dict) else start_state
)
# grid and solver
N = int(self.pattern_config["sim_parameters"]["n_points"])
s_grid = np.linspace(
self.pattern_config["sim_parameters"]["start_angle"],
self.pattern_config["sim_parameters"]["end_angle"],
N + 1,
)
qs_solver = self.residual_solver(km_copy)
# pack initial guesses / states
if self.quasi_steady:
# z = [tension_tether_ground, input_steering, s_dot, speed_radial]
z = ca.vertcat(
state_obj.tension_tether_ground,
state_obj.input_steering,
state_obj.s_dot,
state_obj.speed_radial,
)
# x = [s, distance_radial]
x = ca.vertcat(s_grid[0], state_obj.distance_radial)
else:
# z = [tension_tether_ground, input_steering, s_ddot, speed_radial]
z = ca.vertcat(
state_obj.tension_tether_ground,
state_obj.input_steering,
0.01, # initial guess for s_ddot
state_obj.speed_radial,
)
# x = [s, s_dot, distance_radial]
x = ca.vertcat(s_grid[0], state_obj.s_dot, state_obj.distance_radial)
lbx, ubx, lbg, ubg = self.get_boundaries(state_obj, unknown_vars, km_copy)
t = float(state_obj.t)
# --- helper: stable Δt from ds, v, a (ds = v*dt + 0.5*a*dt^2)
def _dt_from_ds_v_a(ds_scalar, v_s, a_s):
"""
Numerically stable positive root:
dt = 2*ds / ( v + sqrt(v*v + 2*a*ds) )
- uses CasADi ops so it works with DM/MX/SX.
- if discriminant < 0: clip to 0 if allow_failure else raise.
"""
disc = v_s * v_s + 2.0 * a_s * ds_scalar
if allow_failure:
disc = ca.fmax(
disc, 0.0
) # clip; produces the limiting solution if negative
else:
# optional hard check
if isinstance(disc, (float, int)) and disc < 0:
raise ValueError(f"Negative discriminant: v^2+2*a*ds={disc}")
denom = v_s + ca.sqrt(disc)
# add tiny epsilon to avoid divide-by-zero when v≈0 and a→0
return 2.0 * ds_scalar / (denom + 1e-12)
# --- main loop
for i in range(N):
# 1) solve residuals at current s-grid node
sol = qs_solver(x0=z, p=x, lbg=lbg, ubg=ubg, lbx=lbx, ubx=ubx)
z = sol["x"] # CasADi DM
# 2) record current state (BEFORE stepping to next s)
if self.quasi_steady:
curr_state = State(
t=t,
s=float(x[0]),
input_steering=float(z[1]),
tension_tether_ground=float(z[0]),
s_dot=float(z[2]),
distance_radial=float(x[1]),
speed_radial=float(z[3]),
)
else:
curr_state = State(
t=t,
s=float(x[0]),
s_dot=float(x[1]),
input_steering=float(z[1]),
tension_tether_ground=float(z[0]),
s_ddot=float(z[2]),
distance_radial=float(x[2]),
speed_radial=float(z[3]),
)
self.states.append(curr_state.to_dict())
# 4) step to next s using appropriate time increment
ds = float(s_grid[i + 1] - s_grid[i]) # scalar number
if self.quasi_steady:
# a_s = 0 => dt = ds / v_s
v_s = z[2] # s_dot from QS solve
dt = ds / (v_s + 1e-12) # small epsilon to avoid division by zero
next_r = x[1] + z[3] * dt
x = ca.vertcat(s_grid[i + 1], next_r)
else:
# dynamic: ds = v*dt + 0.5*a*dt^2
v_s = x[1] # current s_dot (state)
a_s = z[2] # current s_ddot (solve result)
dt = _dt_from_ds_v_a(ds, v_s, a_s)
next_s_dot = v_s + a_s * dt
next_r = x[2] + z[3] * dt
x = ca.vertcat(s_grid[i + 1], next_s_dot, next_r)
# 5) advance time (dt is a CasADi scalar DM; cast to float)
t += float(dt)
print("Total time:", t)
return self.states if return_states else None
def run_simulation_euler(
self, start_state, allow_failure=True, return_states=False
):
# print("Starting state:", start_state)
self.substitute_parametrized_kinematics()
self.states = []
self.kite_model.reset_solver()
if self.quasi_steady:
unknown_vars = ["length_tether", "input_steering", "s_dot", "speed_radial"]
else:
unknown_vars = ["length_tether", "input_steering", "s_ddot", "speed_radial"]
if self.kite_model.is_tether_rigid:
unknown_vars[0] = "tension_tether_ground"
# Initialize state
if isinstance(start_state, dict):
state_obj = State(**start_state)
else:
state_obj = start_state
N = self.pattern_config["n_points"]
time_step = self.pattern_config["end_time"] / self.pattern_config["n_points"]
qs_solver = self.residual_solver()
if self.quasi_steady:
z0 = ca.vertcat(
state_obj.tension_tether_ground,
state_obj.input_steering,
state_obj.s_dot,
state_obj.speed_radial,
)
x0 = ca.vertcat(state_obj.s, state_obj.distance_radial)
else:
z0 = ca.vertcat(
state_obj.tension_tether_ground,
state_obj.input_steering,
0,
state_obj.speed_radial,
)
x0 = ca.vertcat(
state_obj.s,
state_obj.s_dot,
state_obj.distance_radial,
)
lbx, ubx, lbg, ubg = self.get_boundaries(state_obj, unknown_vars)
t = self.pattern_config["start_time"]
for i in range(N):
# print(f"Time: {t}, State: {x0}, Inputs: {z0}")
if self.quasi_steady:
sol = qs_solver(x0=z0, p=x0, lbg=lbg, ubg=ubg, lbx=lbx, ubx=ubx)
z0 = sol["x"]
new_s = x0[0] + z0[2] * time_step
new_r = x0[1] + z0[3] * time_step
x0 = ca.vertcat(new_s, new_r)
else:
sol = qs_solver(x0=z0, p=x0, lbg=lbg, ubg=ubg, lbx=lbx, ubx=ubx)
z0 = sol["x"]
new_s = x0[0] + x0[1] * time_step
new_s_dot = x0[1] + z0[2] * time_step
new_r = x0[2] + z0[3] * time_step
x0 = ca.vertcat(new_s, new_s_dot, new_r)
if self.quasi_steady:
new_state = State(
t=t,
s=x0[0],
input_steering=float(z0[1]),
tension_tether_ground=float(z0[0]),
s_dot=float(z0[2]),
distance_radial=float(x0[1]),
speed_radial=float(z0[3]),
)
else:
new_state = State(
t=t,
s=x0[0],
s_dot=float(x0[1]),
input_steering=float(z0[1]),
tension_tether_ground=float(z0[0]),
s_ddot=float(z0[2]),
distance_radial=float(x0[2]),
speed_radial=float(z0[3]),
)
t += time_step
self.states.append(new_state.to_dict())
def opti_phase(
self,
start_state,
opti=None,
start_state_opti=None,
opti_params=None,
relax_tol=0.0,
):
if not opti:
opti = ca.Opti()
self.run_simulation_phase(start_state, return_states=True)
self.kite_model.reset_solver()
if start_state_opti:
start_state = start_state_opti
# initial state object
state_obj = (
State(**start_state) if isinstance(start_state, dict) else start_state
)
# Replace optimized parameters with symbolic variables
path_params = copy.deepcopy(self.pattern_config_opti.get("path_parameters", {}))
radial_params = copy.deepcopy(
self.pattern_config_opti.get("radial_parameters", {})
)
sim_params = copy.deepcopy(self.pattern_config_opti.get("sim_parameters", {}))
pattern = create_pattern_from_dict(
self.pattern_config_opti["pattern_type"], path_params
)
N = int(sim_params["n_points"])
tau = ca.DM(np.linspace(0, 1, N + 1)) # numeric grid (DM column vector)
s0 = sim_params["start_angle"] # can be float or MX
s1 = sim_params["end_angle"] # MX (Opti variable) in your case
# Symbolic affine map: s_grid is MX because s1 is MX
s_grid = s0 + (s1 - s0) * tau
winch_model = Winch(pattern_config=radial_params)
km_copy = self.substitute_parametrized_kinematics(pattern)
self.km_param = km_copy
# --- Decision variables per node (N nodes for intervals 0..N-1)
opti_vars = {
"s": s_grid,
"s_dot": opti.variable(N), # tangential speed
"input_steering": opti.variable(N),
"speed_radial": opti.variable(N), # reel speed v_r
"distance_radial": opti.variable(N), # radius r
"tension_tether_ground": opti.variable(N), # tether tension T
}
# # expose design params too
# for var in self.optimization_vars:
# opti_vars[var] = self.optimization_vars[var]
# --- Helper to check warm start against bounds
def check_warm_start(var_name, values, bounds):
if not bounds or len(bounds) != 2:
return
lb, ub = bounds
values = np.asarray(values).ravel()
violations_lb = values < lb
violations_ub = values > ub
if np.any(violations_lb) or np.any(violations_ub):
n_violations = np.sum(violations_lb) + np.sum(violations_ub)
print(
f"Warning: Warm start for {var_name} violates bounds in {n_violations} points"
)
if np.any(violations_lb):
min_val = np.min(values[violations_lb])
print(f" - Below lower bound ({lb}): min value = {min_val}")
if np.any(violations_ub):
max_val = np.max(values[violations_ub])
print(f" - Above upper bound ({ub}): max value = {max_val}")
# --- Warm starts from simulation (with bound checking)
warm_starts = {
"s_dot": self.return_variable("s_dot"),
"input_steering": self.return_variable("input_steering"),
"speed_radial": self.return_variable("speed_radial"),
"distance_radial": self.return_variable("distance_radial"),
"tension_tether_ground": self.return_variable("tension_tether_ground"),
}
print("\nChecking warm start values against bounds:")
for var_name, values in warm_starts.items():
# Check against optimization bounds if defined
if var_name in DEFAULT_OPTI_LIMITS:
check_warm_start(var_name, values, DEFAULT_OPTI_LIMITS[var_name])
# Set the initial value regardless of violations
opti.set_initial(opti_vars[var_name], values)
# # Fix initial radius
opti.subject_to(opti_vars["distance_radial"][0] == state_obj.distance_radial)
# --- Build model functions
km_copy.establish_residual()
flat_syms = [ca.vertcat(*opti_params.values())] if opti_params else []
residual = ca.Function(
"residual",
[
self.s,
self.s_dot,
km_copy.input_steering,
km_copy.tension_tether_ground,
km_copy.speed_radial,
km_copy.distance_radial,
]
+ flat_syms,
[km_copy.residual],
)
tether_tension_eq = ca.Function(
"tether_tension_eq",
[
self.s,
self.s_dot,
km_copy.input_steering,
km_copy.speed_radial,
km_copy.distance_radial,
km_copy.tension_tether_ground,
]
+ flat_syms,
[km_copy.tension_tether_equation],
)
# --- Safety / geometry constraint
height = pattern.z(opti_vars["distance_radial"], s_grid[:-1]) # N entries
opti.subject_to(height >= 50)
# --- Power scale based on the simulated trajectory (LEFT RULE, consistent)
t_hist = self.return_variable("t") # length N (QS) or N+1
P_hist = self.return_variable("mechanical_power") # same length
dt_hist = np.diff(t_hist) # length N-1
E0 = float(np.sum(P_hist[:-1] * dt_hist)) # left Riemann sum
T0 = float(np.sum(dt_hist))
P0 = E0 / (T0 + 1e-12)
P_scale = max(abs(P0), 1.0)
# --- Auto scales from warm start (robust to outliers)
def _scale(x, floor=1.0):
x = np.asarray(x).ravel()
if x.size == 0:
return float(floor)
s = np.percentile(np.abs(x), 90) # “typical large” value
return float(max(s, floor))
r_hist = self.return_variable("distance_radial")
vr_hist = self.return_variable("speed_radial")
sd_hist = self.return_variable("s_dot")
T_hist = self.return_variable("tension_tether_ground")
u_hist = self.return_variable("input_steering")
S = {
"r": _scale(r_hist, floor=1.0),
"vr": _scale(vr_hist, floor=1.0),
"sd": _scale(sd_hist, floor=1.0),
"T": _scale(T_hist, floor=1.0),
"u": _scale(u_hist, floor=1.0),
}
# Residual equation scales (fallback: tie to tension scale)
S_res = [max(S["T"], 1.0)] * 3
# --- Helpful bounds to keep NLP well-posed
sdot_min = 1e-2 # ensures dt>0
opti.subject_to(opti_vars["s_dot"] >= sdot_min)
if "speed_radial" in DEFAULT_OPTI_LIMITS:
lb, ub = DEFAULT_OPTI_LIMITS["speed_radial"]
opti.subject_to(opti_vars["speed_radial"] >= lb)
opti.subject_to(opti_vars["speed_radial"] <= ub)
if "distance_radial" in DEFAULT_OPTI_LIMITS:
lb, ub = DEFAULT_OPTI_LIMITS["distance_radial"]
opti.subject_to(opti_vars["distance_radial"] >= lb)
opti.subject_to(opti_vars["distance_radial"] <= ub)
# --- Objective assembly with SAME quadrature as simulation (left rule)
energy = 0
t_eff = 0
for i in range(N):
# Model tension at node i
T_i = tether_tension_eq(
s_grid[i],
opti_vars["s_dot"][i],
opti_vars["input_steering"][i],
opti_vars["speed_radial"][i],
opti_vars["distance_radial"][i],
opti_vars["tension_tether_ground"][i],
*flat_syms,
)
T_model = winch_model.tension_curve(opti_vars["speed_radial"][i])
# Scale the tether law residual
opti.subject_to((T_i - T_model) / S["T"] == 0)
# Residual equations (scaled)
res_i = residual(
s_grid[i],
opti_vars["s_dot"][i],
opti_vars["input_steering"][i],
T_i,
opti_vars["speed_radial"][i],
opti_vars["distance_radial"][i],
*flat_syms,
)
opti.subject_to(res_i[0] / S_res[0] == 0)
opti.subject_to(res_i[1] / S_res[1] == 0)
opti.subject_to(res_i[2] / S_res[2] == 0)
# Left-rule dt_i = Δs_i / s_dot[i], guarded to avoid blow-up
if i < N - 1:
ds_i = s_grid[i + 1] - s_grid[i]
sd_safe = ca.fmax(opti_vars["s_dot"][i], max(sdot_min, S["sd"] * 1e-3))
dt_i = ds_i / sd_safe
# r_{i+1} propagation (scaled residual)
opti.subject_to(
(
opti_vars["distance_radial"][i + 1]
- opti_vars["distance_radial"][i]
- opti_vars["speed_radial"][i] * dt_i
)
/ S["r"]
== 0
)
# Accumulate energy and time: power_i = T_i * v_r_i
energy += T_i * opti_vars["speed_radial"][i] * dt_i
t_eff += dt_i
power = energy / (t_eff + 1e-12)
# --- Tiny Tikhonov regularization in scaled variables (stabilizes curvature)
eps = 1e-6
reg = eps * (
ca.sumsqr(opti_vars["input_steering"] / S["u"])
+ ca.sumsqr(opti_vars["s_dot"] / S["sd"])
+ ca.sumsqr(opti_vars["speed_radial"] / S["vr"])
)
# --- Initials for optimization parameters
for var, mx in opti_params.items():
if var in self.pattern_config["path_parameters"]:
init_val = self.pattern_config["path_parameters"][var]
opti.set_initial(mx, init_val)
# print(f"Applying constraints for {var}")
lb, ub = DEFAULT_OPTI_LIMITS[var]
opti.subject_to(mx >= lb)
opti.subject_to(mx <= ub)
elif var in self.pattern_config["radial_parameters"]:
init_val = self.pattern_config["radial_parameters"][var]
opti.set_initial(mx, init_val)
# print(f"Setting initial for {var} to {init_val}")
lb, ub = DEFAULT_OPTI_LIMITS[var]
# print(f"Applying constraints for {var}: lb={lb}, ub={ub}")
opti.subject_to(mx >= lb)
opti.subject_to(mx <= ub)
elif var in self.pattern_config["sim_parameters"]:
init_val = self.pattern_config["sim_parameters"][var]
opti.set_initial(mx, init_val)
# print(f"Applying constraints for {var}")
lb, ub = DEFAULT_OPTI_LIMITS[var]
opti.subject_to(mx >= lb)
opti.subject_to(mx <= ub)
# else:
# raise ValueError(
# f"Optimization parameter '{var}' not found in 'path_parameters' or 'radial_parameters'."
# )
# --- Default limits for vector vars (if provided)
for var_name, mx in opti_vars.items():
if isinstance(mx, ca.MX) and var_name in DEFAULT_OPTI_LIMITS:
# print(f"Applying constraints for {var_name}")
lb, ub = DEFAULT_OPTI_LIMITS[var_name]
if relax_tol > 0:
# expand bounds outward even if bounds are negative
lb = lb - relax_tol * np.abs(lb)
ub = ub + relax_tol * np.abs(ub)
if mx.shape[0] == N:
opti.subject_to(lb <= mx[:])
opti.subject_to(mx[:] <= ub)
else:
opti.subject_to(lb <= mx)
opti.subject_to(mx <= ub)
angle_elevation = pattern.elevation(opti_vars["distance_radial"], s_grid[:-1])
objective_dict = {
"energy": energy,
"total_time": t_eff,
"power_scale": P_scale,
"reg": reg,
"angle_elevation_start": angle_elevation[0],
"angle_elevation_end": angle_elevation[-1],
}
return (
opti,
opti_vars,
objective_dict,
)
def run_simulation_opti(self, opti, objective):
# Keep your solver choice; just add reg to the objective
opti.minimize(objective)
# --- Solver (UNCHANGED as requested)
opti.solver(
"ipopt",
{
"ipopt": {
"bound_relax_factor": 1e-8,
"tol": 1e-4,
"acceptable_iter": 3,
"acceptable_tol": 1e-4,
"constr_viol_tol": 1e-4,
"dual_inf_tol": 1e-4,
"hessian_approximation": "limited-memory",
"mu_strategy": "adaptive",
}
},
)
try:
solution = opti.solve()
# stiffness_report(opti, solution, name="My OCP")
print("\nOptimized Pattern Variables:")
for var_name, mx in self.optimization_vars.items():
val = solution.value(mx)
print(f" {var_name}: {val}")
# write back optimized parameters
optimized_config = self.pattern_config.copy()
if var_name in optimized_config["path_parameters"]:
optimized_config["path_parameters"][var_name] = solution.value(mx)
elif var_name in optimized_config["radial_parameters"]:
optimized_config["radial_parameters"][var_name] = solution.value(mx)
elif var_name in optimized_config["sim_parameters"]:
optimized_config["sim_parameters"][var_name] = solution.value(mx)
self.pattern_config = optimized_config
return solution
except Exception as e:
print("Debug optimization information:")
for var_name, mx in self.optimization_vars.items():
try:
print(f" {var_name}: {opti.debug.value(mx)}")
except Exception:
pass
print("Optimization failed:", e)
def substitute_parametrized_kinematics(self, pattern):
kinematics = ParametrizedKinematics(pattern, self)
km_copy = copy.deepcopy(self.kite_model)
km_copy.angle_course = kinematics.chi
# Optimal analytical solution for speed_radial should be part of the pattern class
# km_copy.speed_radial = km_copy.speed_radial
# print(km_copy.speed_radial)
# km_copy.speed_radial = kinematics.vr
km_copy.speed_tangential = kinematics.vtau
km_copy.timeder_angle_course = kinematics.dot_chi
if not self.quasi_steady:
km_copy.timeder_speed_radial = kinematics.dot_vr
km_copy.timeder_speed_tangential = kinematics.dot_vtau
else:
km_copy.timeder_speed_radial = 0
km_copy.timeder_speed_tangential = 0
km_copy.angle_azimuth = kinematics.phi
km_copy.angle_elevation = kinematics.beta
return km_copy
def integrator(self, time_step, kite_model=None):
if kite_model is None:
kite_model = self.kite_model
kite_model.establish_residual()
if self.quasi_steady:
x = ca.vertcat(self.s, kite_model.distance_radial)
if kite_model.is_tether_rigid:
z = ca.vertcat(
kite_model.tension_tether_ground,
kite_model.input_steering,
self.s_dot,
)
else:
z = ca.vertcat(
kite_model.length_tether,
kite_model.input_steering,
self.s_dot,
)
ode = ca.vertcat(
self.s_dot,
)
else:
x = ca.vertcat(
self.s,
self.s_dot,
kite_model.distance_radial,
)
if kite_model.is_tether_rigid:
z = ca.vertcat(
kite_model.tension_tether_ground,
kite_model.input_steering,
self.s_ddot,
)
else:
z = ca.vertcat(
kite_model.length_tether,
kite_model.input_steering,
self.s_ddot,
)
ode = ca.vertcat(
self.s_dot,
self.s_ddot,
)
alg = kite_model.residual
alg = ca.vertcat(
alg,
self.winch_model.radial_equation(
tension_tether_ground=kite_model.tension_tether_ground,
speed_radial=kite_model.speed_radial,
),
)
z = ca.vertcat(z, kite_model.speed_radial)
ode = ca.vertcat(ode, kite_model.speed_radial)
dae = {"x": x, "z": z, "ode": ode, "alg": alg}
# Create the integrator
opts = {
"abstol": 1e-6,
"reltol": 1e-6,
# "max_num_steps": 20000,
# "max_step_size": 0.01, # Or even 1e-3 if very stiff
}
# intg = ca.integrator("intg", "idas", dae, opts)
intg = ca.integrator("intg", "idas", dae, 0, time_step, opts)
return intg
def residual_solver(self, km_copy=None):
if km_copy is None:
km_copy = self.kite_model
km_copy.establish_residual()
if self.quasi_steady:
if km_copy.is_tether_rigid:
z = ca.vertcat(
km_copy.tension_tether_ground,
km_copy.input_steering,
self.s_dot,
)
else:
z = ca.vertcat(
km_copy.length_tether,
km_copy.input_steering,
km_copy.s_dot,
)
p = ca.vertcat(
self.s,
km_copy.distance_radial,
)
else:
if km_copy.is_tether_rigid:
z = ca.vertcat(
km_copy.tension_tether_ground,
km_copy.input_steering,
self.s_ddot,
)
else:
z = ca.vertcat(
km_copy.length_tether,
km_copy.input_steering,
self.s_ddot,
)
p = ca.vertcat(
self.s,
self.s_dot,
km_copy.distance_radial,
)
alg = km_copy.residual
alg = ca.vertcat(
alg,
self.winch_model.radial_equation(
tension_tether_ground=km_copy.tension_tether_ground,
speed_radial=km_copy.speed_radial,
),
)
z = ca.vertcat(z, km_copy.speed_radial)
nlp = {
"x": z,
"f": 0,
"g": alg,
"p": p,
}
solver_options = {
"ipopt": {
"print_level": 0, # Suppresses IPOPT output
"max_iter": 200, # Maximum number of iterations
"sb": "yes", # Suppresses more detailed solver information
},
"print_time": False, # Disables CasADi's internal timing output
}
return ca.nlpsol("solver", "ipopt", nlp, solver_options)
def get_boundaries(self, state_obj, unknown_vars, km_copy):
lbx, ubx, lbg, ubg = km_copy.get_boundaries(state_obj, unknown_vars)
return lbx, ubx, lbg, ubg
import casadi as ca
import numpy as np
def register_opti_vars(obj, store=None, *, name_prefix=None):
"""
Recursively scan `obj` (dict/list/tuple/numpy/MX) for CasADi MX symbols
and add their leaf variables (via ca.symvar) to `store` exactly once.
Parameters
----------
obj : any
Container (dict/list/tuple/ndarray) or MX expression/symbol.
store : dict | None
Mapping name -> MX to update (created if None).
name_prefix : str | None
If set, only add variables whose .name() starts with this prefix (e.g. "opti").
Returns
-------
dict : updated store
"""
if store is None:
store = {}
def _scan(x):
# Base cases
if isinstance(x, ca.MX):
# collect leaf symbols from the expression/symbol
for v in ca.symvar(x):
nm = v.name()
if (
name_prefix is None or nm.startswith(name_prefix)
) and nm not in store:
store[nm] = v
return
# Recurse into common containers
if isinstance(x, dict):
for v in x.values():
_scan(v)
elif isinstance(x, (list, tuple, set)):
for v in x:
_scan(v)
elif isinstance(x, np.ndarray):
for v in x.flat:
_scan(v)
# else: ignore scalars/others
_scan(obj)
return store